The field of transport uses composite materials in order to benefit from their lightness while ensuring optimal mechanical strength. Some composite materials include an organic matrix reinforced by a fiber preform. The latter can include a stack of fiber plies woven together using interlacing threads.
The mechanical strength provided by a composite of this type can be estimated by means of software. This theoretical strength is based on a predetermined model of thread orientation. In reality, the threads exhibit positioning errors, due for example to imprecise positioning of the plies, and safety factors are therefore required. These factors are integrated into the mechanical strength calculations in order to reduce the expected strength, with the result that the corresponding composite component has to be overdesigned.
In the case of a composite wall, the effect is to increase its thickness. This solution is unsatisfactory, particularly in the field of aeronautics, because it also increases the payload and has a direct effect on fuel consumption. The compactness is reduced, while safety is not necessarily ensured.
The document FR 2 995 553 A1 discloses a method for making a preform for a fan retention casing of a gas turbine designed for aeronautical use. The method comprises the winding of a fibrous structure onto a winding mandrel. The fibrous structure comprises tracing threads that enable the alignment of the structure to be monitored in real time by means of a camera. The real-time analysis can be used to invalidate a winding, preventing the subsequent use of a preform which is out of tolerance. However, this method requires the generation of rebuses, the proportion of which increases with the number of stacked fibrous layers, or the complexity of the shapes to be produced.